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Accelerated diffusion of alkanes between cavities

Applications

IN11 is primarily used to study slow relaxation phenomena in polymers, glasses, complex liquids or magnetic materials. Elastic paramagnetic scattering may be studied as well by polarization analysis. Under normal working conditions, a low field of 1-2 Gauss is used on the sample, but experiments in magnetic fields up to 2 T are also possible. A graphite energy analyser crystal can optionally be installed in front of the detector (triple axis spectrometer configuration), if better momentum transfer resolution is required. The spectrometer can also be used to determine the linewidth of elementary excitations if the dispersion is flat. Typical applications are

  • Reptation in polymer melts
  • Alpha relaxation in glass-forming polymers
  • Dynamics in micellar solutions
  • Diffusion of water or other molecules in confining media
  • Magnetic excitations and relaxation dynamics
  • Spin glass dynamics
  • Phonon linewidth

Accelerated diffusion of alkanes between cavities

With the large time range and high intensity available by combining IN11 and IN15 it was possible to verify the “window effect”, a geometrical enhancement of the diffusivity of molecules with an intermediate size.

Diffusivity of linear alkanes in various zeolites as a function of the number of carbon atoms. a) NaX zeolite by PFG NMR, b) ZSM-5 by QENS and c) zeolite 5A by IN11 and IN15 (H. Jobic et al., Angew. Chem. 43 (2004) 364).